A group called End Citizens United rolled out an ad accusing Heck of supporting Wall Street and oil interests that fund his campaign. And a group with ties to Reid released a commercial suggesting Heck wants to risk seniors’ retirements on the stock market.

Heck’s campaign says the groups’ ads are misleading, and accused his Democratic opponent Catherine Cortez Masto of being hyper-partisan during her time as Nevada’s attorney general.

Nevada’s Senate race is key in the fight for control of the Senate, and ranks fourth among this cycle’s Senate races for outside spending.

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